Positioning edge loops with precision
The factor of the Edge Loop is a value between -1 and 1. Assuming you know the total length of the wall (w), and (x) is the distance from the corner,  you can use this formula :

factor = 1-x/w*2


To enter the formula, press the = while using the loopcut tool, then type your values.

But this is tedious, cause the total length will be reduced by each cut. It would be much easier to extrude faces starting from the left, because extrude allows to specify distance values.